Historically, maps were printed on paper or other non-modifiable, non-interactive media. There were essentially two forms of recourse when a map needed modification: 1) to enter a correction by hand on the paper copy; or 2) to reprint the map with the correction made on the original. Manual corrections are time-intensive, particularly for multiple modifications, and by definition do not update any of the other outstanding copies of the map. The option of reprinting the map is expensive and also an impractical way to respond to frequent modifications.
In the current age, we have databases, documents and maps in digital, electronic formats, capable of being updated as desired and able to respond to a selected range and type of operator input and to produce operator-requested output. Many electronic documents and electronic databases in common usage today comprise information related to geographic location(s). Indeed, it is not necessarily easy to think of a class of electronic documents or a class of electronic databases that does not at least occasionally incorporate some form of geographically related information.
One example of electronic databases that is relevant to certain embodiments of the invention is geospatial databases, known for convenience and intuitive comprehensibility as electronic maps or digital map databases. In the current computer age, maps have evolved well beyond their centuries-old status as static paper depictions of a non-adjustable data set as recorded at one particular time. For simplicity, much of the discussion below refers to electronic maps, although the points made also apply to electronic documents and electronic databases other than maps. In this application, the term digital map database is used to denote all kinds of electronic and digital maps.
One of the great benefits of a digital map database over a traditional paper-based map is its inherent flexibility and ability to portray large amounts of data. Paper maps are necessarily limited in the amount and type of information they can portray, within the constraints of their physical formats. Paper maps are also difficult to update.
Digital map databases do not suffer from these problems. While earlier digital maps may have seemed merely like a scanned version of the paper product, today's modern digital map databases are much more powerful. Unlimited amounts of information can be included in the map and either displayed, or not displayed, depending on the wishes of the user.
Today's digital map databases, also known as electronic maps, can allow for regular modification of data points included in the digital map database as well as active user selection of desired geographic features of interest. As new information arises, of a type specifically relevant to a map of interest or a point of interest in the map the map can be quickly updated to reflect changes or corrections to all or just a small subset of locations.
Today's digital map databases, also known as electronic maps are being made or updated in a manual process at a map production site. After the compilation or updating process has been finalized, the digital map database is released. After the release the digital map database or a part thereof goes in a conversion or compilation process resulting in a digital map product which can be used by a certain application (such as a mobile navigation device). Whereas updating the digital map database in the production site is a well known process, updating the digital map database for the application is more complicated. As a consequence, most of the digital map database updating currently takes place at the production site after which the release and conversion process follows leading to a complete application digital map database containing the updated information. This is a cumbersome process. In an alternative process the updates are made at the production site and portions of the updated digital map database are transferred to the application digital map database and replace the outdated portions there. Such a process is generically referred to as advanced map updating.
Different ways of advanced map updating exist and have been prototyped. These include incremental updating in which the individual map updates are communicated to a system deploying the map in an application and integrated in the map and regional updating in which a subset of the map coverage is completely replaced by a more current version of that subset or other forms of partial updates.
In practise these methods however are not applied frequently due to their complex technical nature. As a result, in the current market place map database providers publish at regular interval updated versions of the map database products sold earlier. In other words, the user can update the map database he uses by exchanging it for a newer version. Due to the costs of making these updates available, updates are only supplied at relatively long intervals and purchased at even longer intervals.
Another way to bypass the complex solution of advanced map updating at the application has been found in another system architecture. In this architecture the map database is no longer present on the navigation device but present on a central server with which the application connects via a wireless medium. Because in this architecture, only one database needs to be updated which can be accessed relatively easy, the problem of updating is less complex. However, this architecture also has disadvantages which have prevented large scale adoption in the market place so far. For instance, the remote map database always needs to be accessible for the navigation device, demanding reliable and expensive communication systems for ensuring communication between the navigation device and the map database. Such communication systems may have difficulties operating successfully in situations involving heavy weather or in remote areas, such as an isolated area outside the range of for instance a telephone antenna. Also, a relatively high amount of data will be transmitted, which may be relatively expensive for a user.
The number of systems in the market with this architecture is still small and it is generally associated with the mobile phone market rather than with the in-car or personal navigation market which are the well developed markets of map databases and which are addressed by the present invention.
As a consequence, most if not all map databases in the market are not updated or updated with very long intervals.
U.S. Pat. No. 7,158,880 describes a navigation system that computes driving directions from a starting position to a destination position based on a basic navigation database initially stored in the navigation system and supplemental navigation data received from a remote location. U.S. Pat. No. 7,158,880 therefore described a navigation system using incremental updating of the digital map database stored in the navigation system.
It is an object to provide a system and method that at least partially overcomes the disadvantages associated with outdated maps.